CopyImageMetadata : Remove todo
CopyImageMetadata : Remove todo

ImageProcessor does now provide an ArrayPlug for `in`, but we have standardised on using that only when all inputs serve a similar purpose (such as in Merge). When a secondary input has different semantics than the rest, it should have its own name. See https://github.com/gafferhq/gaffer/wiki/Node-Design-Guidelines.

hradec/gaffer,hradec/gaffer,johnhaddon/gaffer,johnhaddon/gaffer,ImageEngine/gaffer,hradec/gaffer,andrewkaufman/gaffer,andrewkaufman/gaffer,GafferHQ/gaffer,johnhaddon/gaffer,andrewkaufman/gaffer,GafferHQ/gaffer,andrewkaufman/gaffer,ImageEngine/gaffer,ImageEngine/gaffer,GafferHQ/gaffer,hradec/gaffer,johnhaddon/gaffer,andrewkaufman/gaffer,GafferHQ/gaffer,johnhaddon/gaffer,ImageEngine/gaffer,hradec/gaffer,GafferHQ/gaffer